The alpha types Can be all strut and no (or only maybe one) fruck. Either way, the quieter betas tend to be far more loyal - increasing the chances for long term relationships
But the Alpha types are just SO charming and EXCITING, they make the girls vaginas tingle.
So too many women marry the loyal beta providers, and either have affairs on the side with the exciting alphas, or party their 20's away with the alphas. and then marry betas later in life when they are no longer attractive enough for the alphas to notice.